This invention relates to information transmission between moving objects and stationary objects. In particular, this invention relates to information arrays between rotating bodies and stationary bodies.
There are numerous reasons that why it is preferable to rotate objects. Such reasons include spin stabilized nose-cones of missiles and tracking radars. The rotating members of these items generate information which is frequently two-dimensional.
Slip rings are the traditional solution to transmit information from the rotating member to a stationary member. A separate slip ring is required for each channel of information to be coupled from the rotating body to the stationary body. Slip ring assemblies provide information linearly proportional to the diameter of the assembly. Assemblies consist of multiple slip rings concentrically mounted. They are stacked to avoid large diameters. The present invention provides information directly proportional to the number of discrete elements in the derotation assembly which is the area of a circle. Thus doubling the diameter in the present invention provides four times as much signal capability as compared to doubling the diameter of a slip ring assembly which only doubles the signal capability. The number of slip rings required for current signal requirements can be over one hundred. The maintenance problems of such devices emphasize the need for an alternate method to the slip ring approach.
Prior art patents, such as U.S. Pat. Nos. 3,428,812 to Burke, 3,586,413 to Adams and 3,977,793 to Trotta, have attempted to provide methods of maintaining stable two-dimensional readout. The patent to Burke used a Dove prism in counterrotating apparatus designed for satellite observations. The patent to Adams requires a looping path to go between surfaces. The patent to Trotta uses a derotating prism to transmit optical signals. All of these prior devices use a half-speed ratio for derotating the final information. Unfortunately, all of these devices are design limited to a specific application.
It is therefor an object of this invention to provide an apparatus that will transmit any type of information between a rotating member and a stationary member with only minor variations in specific components of the apparatus.